Automatic fuse device



2 Quota-Sheet 2 L. R RICARDO 5r AL. AUTOIAT-IG FUSE DEVICE Filed May 18, 1923 July 27 1926.

Patented July 27, 1926.

UNITED STATE PATENT ;o FF c;E. f-

noursnonnroun zmomno AND nonutro IBARRERA,I OF, Morton, ml.

Au'roMaTic FUSE DEVICE.

Application filed May 18, 1923, Serial No. 639,952, and in Cuba october'a, '19221" This invention relates to a protecting device in general and more particularly for telephone and telegraph apparatus and has, as one of its principal objects, to'provide a device which, when placed between the exterior line and a connected apparatus, will preventa current of excessivepower, caused, for example by an electric discharge, from damaging the connected apparatus.

Another object of the invention is to provide a protector which includes-more than one fuse for each'line wire and is adapted to automatically establish a connection includinga fuse, while successively cutting out a fuse,and permanently maintaining a connection between a fuse'and the respective ex terior line wire. I 7

Another object of the. invention is to pro vide a device that is applicable to apparatuses of telegraph and telephone centrals,

simplifies supervision of the same, and prevents prohibitive installation costs.

Other advantages and considerations are contained in the specification, considered in connectlon with'the attached drawings, in

which like characters of reference, designate with the casing removed; f

Fi re'7 is aplan view of thedevice with the fuses of one line wire, melted, Figure "8' is a partial plan view of one form-of device as applied to" atelephonic apparatus;

Figure 9 'is a partial topviewlofanother form of thedevice as applied to'a telephonic apparatus Figure 10fis' a partial plan" View, illustrating a form to test operativeness of theide V106, h n 7 In the drawings, the device is shown as mounted on a rectangular base plate 1 made of insulatingmaterial and having, in its by means of screws 1. At oneend of tl'ie Flgure 6 is an end elevation of the device corners, holes 1" for adequately fastening it plate, centrally and lengthwise thereto, isse f cured a rectangular block 2 of insulating material. To each side of one endof'block 2 isfixed, at their ends, three leaf's'pr'ing contacts 3, 4, 5 and "6 and 7 and 8, placed tiald springs are separated from each "other 9 and I2; "'lhesei'partsare secured together one over the other, the free ends of such springs being slightly curved outwardly."

by means of bolts 15 and 16, which pass? through tubular i ing" covers 15" and 16 within apertures in the block 2. Wires l7 and 18 are connected respectively, at one end, to the springs 5 and 8, outside of the in} sulating tube 15, and in the case of wire 17, between the plate 5 and'an insulating washer 15 (see Fig. 2), which washer'fits over the "insulating tube 15; and atthe other end to binding posts 19 and 20, to whicha-re'co'n- The length of the springs 3, 4, 5 and 6, 7,

and '8 varies, the longest being the inner springs 3 and 6,followed in length by the? neoted wires 21 and 22 connecting up the apparatus that the device is destined to pro intermediate springs 4 and 7, and by the shortest springs 5 and 8 on theoutside. On the interior facesof springs 45, 5, 7, and 8 are projecting contact blocks 23, 2d, and 25,

placed 'leafispring's 27and 28:, joined to wardly.

he springs'3, 4,

5, 5,7 and 8, are pro- 38, '39, 4:0 and 4:1,"the other endsof which dle-shaped brackets 48 and 49, fixed length wise of base land on'either side ofthe same by means of bolts 50, 51, 52, and 53 passing through the horizontal flanged ends of each bracket; The fuses, connected to the springs and froin' the small plates 27 i and '28, maintaininga'spring tension in the same.

Near the front of base 1, a longnarrow plate,

54 is "fixed'by'" means of screws'55 which hold 26. 'Within the free ends of the inner springs 3 and 6, at each sideof block 2, are p gether by a conducting pin 29,'across the" front part ofblock 2, the free ends ofthe springs 27 and28 being'curved slightly 'invided ontheir'eXterio'r faces at the free ends, with lugs 30,31, 32, 33, 3e and 35,]to which "areconnected the ends of the fuses 36, 37,

" 3--8, hold them separated from one another, 1

it somewhat above the 'base (Fig. 4)" the plate 5 1 having one of its edges serrated as indicated at 54: and on which edge, near the ends of the plate, are semicircular notches, 54L. Immediately opposite plate 5 1, and spaced a slight distance therefrom, are placed two angular plates 56 and 57, fixed to the base by means of screws 58 and 59, which hold them also, a distance above base 1 equal to that of the adjacent plate 5 1. The shorter branches of plates 56 and 57 are directed away from plate 5 1-, and their longer branches are in line and slightly separated from each other, and have at their ends, opposed semicircular notches 74, the said plates having those edges corresponding to the serrated edge ot' plate 54, likewise ser ated, as shown at 56 and 57. They present near their outer ends, semicircular notches 56 and 57", corresponding with the notches 54; in plate 54-, and forming plug sockets therewith, an object to be later explained.

The ends of the short branches of the plates 56 and, 5,7 are secured to brackets 60 and 61 by means of bolts 62 and 63, the heads 0t which constitute binding posts to which are connected, above, wires 64 and 65 which connect to the exterior line and below by wires 64; and 65, with the lower heads of bolts 50 and 52.

At the end of the base 1, are connected respectively to 62 and 63 by wires 85 and 86, binding-posts 66 and 67, the post 66 being connected by means of a wire 68 with one end of a bolt 69 passing through the front end of block 2, the post 67 being connected by means of a wire 70 with one head of bolt 29, which secures the small plate contacts 27 and 28.

Between the binding-posts 66 and 67 is a post 71, of a ground. line, which, by means of a wire 7 2, that passes between the separated ends of the larger branches of the angular plates 56 and 57 connects with a post 7 3 in the center of plate 54.

By means of pins and 76, as should be clear to experts in the art to which this invention appertains, distinct proofs of the operation of the exterior line are obtained by using the pins to complete a circuit through the exterior line by connecting up plate 54 with plates 56 and 57. the normal functioning oi the apparatus however, re quiring holding these pins in their inoperative positions, each in a bore, as 77 (Fig. 10) in base 1.

The more delicate parts of the apparatus are protected by means of a casing 79, provided with handles 80.

The operation of the apparatus is as follows:

Assuming the parts to be in the position shi'iwn in lligure 2, and the device placed between the line and an apparatus to be protected, the current flows by way of the conductors 64 and 65, assuming the conductor 64, as positive flow will be through 64, conductor bracket 18, :tuse 38, spring 5, conductor 17, and wire 21, to the apparatus and back from the apparatus, on the opposite side of base 1, to conductor 65.

In case a current of too great power be produced, due, for instance, to an electric discharge, in a corresponding exterior line, the discharge would be received, and its etfect diminished, in the plate 56, and upon the fuse 38 being melted, contact 5 will be released and will establish contact with the contiguous spring at by means oi? the contact block 23, and current can then circulate through fuse 37 and the two connected plates 5 and 4, and to the wire 21, which leads to the apparatus, as before, and return to conductor 65. On the melting oi. fuse 37, due to a second excess current, the two plates 4 and 5 which are in contact, will establish connection with the contiguous plate 3, and the current will then flow through fuse 36 and the three plates in contact, 3, 4 and. 5, and to the line 21 and return to 65. Furthermore, should the third fuse 36, also melt trom a similar cause, referring to a telegraphic circuit, the plate 3 will contact with the small plate 27, and this, in its turn, with the bolt 69, thus circulating the exterior cur rent "from the binding-post 64; through 85, to 66, passing by wire 68 across the bolts 69 and 29, continuing by the wire 70 to the binding-post 67 and thence to 63 by means of wire 86, as shown in Figure 9, the circuit thus remaining direct between the other stations, but leaving this )artic ular apparatus short circuited from the protecting device.

WVhen dealing with centrals or telephonic apparatuses, as in Figure 8, a bell or alarm device 81 can be connected, with its dry cell 82, by means of wires 83 and 8 1, with binding-posts 66and 67 and on the last fuse of either of the two lead in wires burning, the circuit and the hell or alarm 81 ives notice to the employee to replace the fuses.

By means of the pegs 75 and. 76, distinct tests of the functioning of the exterior line, 01. the device, and oi? the central or apparatus in combination with which it is used, are effected.

Thus, it the existence of any interrupthm in either of the wires 64 or 65 of the exterior line is suspected, in the telegraphic circuit, and assuming it be in wire 641, a metallic plug is introduced in the bore formed by the semi-circular notches 56 and 54", and if any current exists between wire 65 and the apparatus, this proves that wire 64 is interrupted, and vice versa if it is the wire 65.

It is evident that many variations can be introduced in the combination of the parts of this device, without departing from the basic idea of the invention, and therefore, I limit myself protection for what is described only in so far as is necessitated by the following claims.

1. A protecting device, comprising, a base, an insulating block on the base, a plurality of leaf spring contacts of varying lengths placed one over the other and insulated from each other, and secured to each side of the block, the contacts decreasing inlength from the block outwardly, conductor brackets, fuses for the contacts, connected between the brackets and the contact free ends and holding said free. ends out of contact with each other against their inherent spring tension, a connection between each bracket and the external line, and between each outer contact and electrical apparatus to be protected, a serrated edged conductor plate fixed to the base, and two opposed, spaced, serrated edged plates fixed to the base, the two opposed plates being connected 'to the external line, a conducting pin in the block, two conducting spring plates fastened to the block and inside of the leaf spring contacts by a second conducting pin, two contacts fixed to the base and connected, one to the conducting pin, and the other to the second conducting pin, a contact on the conductor plate connected to ground, and a contact on the base connected to the contact on the conductor plate, the conducting spring plates connecting with the longest leaf springs upon the melting of the longest leaf springs fuses.

2. A rotecting device comprising a base, an insu ating block on the base, a plurality of leaf spring contacts of varying lengths placed one over the other and insulated from each other and secured to each side of the block, the contacts decreasing in length from the block outwardly, conductor brackets, fuses for the contacts connected between the brackets and the contact free ends and holding said free ends out of contact with each other against their inherent spring tension, a connection between each bracket and the external line and between each outer contact and electrical apparatus to be protected, a conducting pin in the block, two

conducting spring plates fastened to the block inside of the leaf spring contacts by means of a second conducting pin, two contacts connected to the external line and fixed.

to the base and connected one to the conducting pin and the other to the second conducting pin, the conducting spring plates connecting with the longest leaf springs on the melting of the fuse of the longest leaf spring.

In testimony whereof, we have signed our names to this specification.

LUIS RODRIGUEZ RICARDO. RODULFO BARRERA. 

